Various apparatus which form and fill gable top paperboard cartons are known in the prior art. For example, the Cherry-Burrell packaging machine, Model H-75, is a standard in the field. The Cherry-Burrell machine forms a paperboard carton having four sides and a bottom, partially folds the upper ends of the sides of the carton into a gable top, fills the carton, and completely folds and seals the gable top. The Cherry-Burrell machine operates continuously in an assembly line-type manner, such that cartons are formed and filled one by one in the machine at stations which each perform a small task on the carton in under one second, before the carton moves on to the next station.
Gable top cartons of this type, though, have disadvantages when they are used to store and dispense liquid products such as milk, juice, etc. Specifically, the gable top can often be difficult to open correctly without accidentally tearing the carton, and, when the top is reclosed, it fails to provide a liquid-tight closure and thus allows spillage of the liquid if the carton is accidentally tipped over or shaken.
Accordingly, it has become desirable to place a releasable closure on a sloping side of the gable top in place of opening the gable top, wherein the closure is more easily opened and is liquid-tight when reclosed. For example, U.S. Pat. No. 4,669,640 to Ando et al. discloses a method of attaching a mouthpiece 34 to a gable top carton 20, wherein the mouthpiece is pushed through an aperture 32 in a sloping side 28 of the gable top carton 20 such that the mouthpiece 34 is held to the side 28 by a flange 46 and retainer lugs 48 of the mouthpiece 34, and wherein the flange 46 is then thermally or ultrasonically fused to the side 28.
U.S. Pat. No. 4,813,578 to Gordon et al. also discloses a method of attaching a pour spout 40 to a gable top carton 10, wherein the spout 40 is first placed on the open gable top such that a flange 46 overlies an opening 30 in the gable top, and wherein the flange 46 is then heated and pressed into contact with the gable top such that the flange 46 adheres to the gable top.
Further, U.S. Pat. No. 4,909,434 to Jones et al. discloses a method of securing a pouring spout 1 to a sloping side 2 of a gable top carton, wherein a hole is first cut in the sloping side 2, wherein the spout 1 is then insetted into the hole such that a flange 6 thereof extends around the hole, wherein a skirt section 4 of the spout 1 is then heated to bend and form a second flange around an opposite side of the hole, and wherein both of the flanges are heated to bond and seal with the material of the side 2.
The above methods of attaching spouts to gable top containers have the disadvantage, among others, that they employ thermal or ultrasonic devices to fasten a spout to a container. Such methods are accordingly relatively energy intensive and thus expensive, and, due to the time often required for thermal or ultrasonic fastening, may be difficult to integrate into the operation of a packaging machine such as the Cherry-Burrell machine.
In view of the above, it is an object of the present invention to provide a method and apparatus for attaching spouts to planar portions of articles such as containers.
It is a further object of the present invention to provide a method and an apparatus for attaching spouts to planar portions of articles, wherein the method and apparatus are relatively non-energy intensive.
It is also an object of the present invention to provide a method and apparatus for attaching spouts to planar portions of articles, which are readily integratable into a standard forming and fitting machine, such as a Cherry-Burrell forming and filling machine.
Another object of the present invention is to provide a method and apparatus for preforming the steps of attaching spouts to planar portions of articles with highly accurate repeated horizontal and vertical positioning of the articles at each step.
A further object of the present invention is to provide a method and apparatus for attaching spouts to planar portions of articles with relatively few break downs and relatively little need for repairs.
The above objects as well as other objects not specifically enumerated are accomplished by a method of attaching a spout to a planar portion of an article in accordance with the present invention. In one aspect of the present invention, the method includes the steps of moving the article successively to at least three stations of a conveyor line, positioning an edge portion of the planar portion at a first predetermined position relative to a hole punch at a first station, punching a hole through the planar portion at the first station, positioning the edge portion at a second predetermined position relative to a bonding site preparer at a second station, preparing a bonding site on the planar portion around the hole at the second station, positioning the edge portion at a third predetermined position relative to a spout applicator at a third station, and attaching a spout to the planar portion about the hole at the third station.
The objects of the invention are also accomplished by an apparatus for attaching a spout to a planar portion of an article. The apparatus includes a hole punch, a first positioning means having a first positioning surface thereon located in a first predetermined position relative to the hole punch for positioning the article relative to the hole punch, a bonding site preparer, a second positioning means having a second positioning surface thereon located in a second predetermined position relative to the bonding site preparer for positioning the article relative to the bonding site preparer, a spout applicator, and a third positioning means having a third positioning surface thereon located in a third predetermined position relative to the spout applicator for positioning the article relative to the spout applicator.
In another aspect of the present invention, the apparatus includes punching means for punching a hole, wherein the punching means punches along a central punching axis. A first positioning means for positioning an edge portion of the planar portion is provided which first positioning means is spaced from the punching axis by a predetermined distance. A bonding agent applying means for applying bonding agent in a circle about a central applying axis, is associated with a second positioning means for positioning the edge portion of the planar portion, wherein the second positioning means is spaced from the central applying axis by the predetermined distance. Further, spout attaching means for attaching a spout is provided such that the spout attaching means has a central attaching axis, and third positioning means for positioning the edge portion of the planar portion is provided, wherein the third positioning means is spaced from the attaching axis by the predetermined distance.
The present invention also relates to an apparatus for attaching a spout to a gable top of a paperboard carton, which includes a hole punch mounted for translation along a punching axis, a first positioning means including a substantially horizontal first positioning surface spaced from the punching axis by a predetermined distance, a glue applicator mounted for rotation about a central gluing axis, a second positioning means including a substantially horizontal second positioning surface spaced from the gluing axis by the predetermined distance, a spout applicator mounted for translation along a spout applying axis, a third positioning means including a substantially horizontal third positioning surface spaced from the spout applying axis by the predetermined axis. This aspect of the present invention also includes three suction cups connected to a source of suction and spring-mounted bar beneath the first, second, and third positioning means respectively. Preferably, the three suction cups are mounted on a single elongated lifting bar extending beneath the first, second, and third positioning means in order to further ensure repeatability of the lifting step.
The present invention also relates to a method of positioning a planar portion of an article, which includes the steps of moving the article relative to a positioning means via moving means. The planar portion of the article is guided between a pair of restraining surfaces of the positioning means, while an edge portion of the planar portion is positioned against a positioning surface of the positioning means. Further, the moving means has an overstroke which is compensated to ensure that the edge of the article is stopped once the edge portion is properly positioned against the positioning surface.
The objects of the present invention are also accomplished by an apparatus for positioning a planar portion of an article, including a positioning means which includes a guide surface, a pair of spaced restraining surfaces, and a positioning surface. A means for moving the article relative to the positioning means is provided and guides an edge portion of the planar portion along the guide surface into a location between the restraining surfaces and positions the edge portion of the planar portion against the positioning surface. Compensating means for compensating for an overstroke of the moving means and for stopping movement of the article once the edge portion of the planar portion is properly positioned against the positioning surface is also provided.